libvirt/docs/formatstoragecaps.rst

.. role:: since

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Storage Pool Capabilities XML format
====================================

.. contents::

Overview
--------

The Storage Pool Capabilities XML will provide the information to determine what
types of Storage Pools exist, whether the pool is supported, and if relevant the
source format types, the required source elements, and the target volume format
types.

Element and attribute overview
------------------------------

A query interface was added to the virConnect API's to retrieve the XML listing
of the set of Storage Pool Capabilities ( :since:`Since 5.2.0` ):

  ``virConnectGetStoragePoolCapabilities``  (`API docs <html/libvirt-libvirt-storage.html#virConnectGetStoragePoolCapabilities>`__)

The root element that emulator capability XML document starts with is named
``storagepoolCapabilities``. There will be any number of ``pool`` child elements
with two attributes ``type`` and ``supported``. Each ``pool`` element may have a
``poolOptions`` or ``volOptions`` subelements to describe the available
features. Sample XML output is:

::

   <storagepoolCapabilities>
     <pool type='dir' supported='yes'>
       <volOptions>
         <defaultFormat type='raw'</>
         <enum name='targetFormatType'>
           <value>none</value>
           <value>raw</value>
           ...
         </enum>
       </volOptions>
     </pool>
     <pool type='fs' supported='yes'>
       <poolOptions>
         <defaultFormat type='auto'</>
         <enum name='sourceFormatType'>
           <value>auto</value>
           <value>ext2</value>
           ...
         </enum>
       </poolOptions>
       <volOptions>
         <defaultFormat type='raw'</>
         <enum name='targetFormatType'>
           <value>none</value>
           <value>raw</value>
           ...
         </enum>
       </volOptions>
     </pool>
     ...
   </storagepoolCapabilities>

The following section describes subelements of the ``poolOptions`` and
``volOptions`` subelements

``defaultFormat``
   For the ``poolOptions``, the ``type`` attribute describes the default format
   name used for the pool source. For the ``volOptions``, the ``type`` attribute
   describes the default volume name used for each volume.
``enum``
   Each enum uses a name from the list below with any number of ``value`` value
   subelements describing the valid values.

   ``sourceFormatType``
      Lists all the possible ``poolOptions`` source pool format types.
   ``targetFormatType``
      Lists all the possible ``volOptions`` target volume format types.